Four people, including Schreffler were arrested.
Shearer's mother gave an emotional statement during the proceedings three years after losing her son.
“I hold you the most responsible for Kolton's death. Had it not been for your senseless actions of luring him there that night, there's no doubt in my mind that he would still be here with us today,” Shearer’s mother said.
“You knew when sending him that message that you would be putting him in a terrible situation. He trusted you, he thought of you as a friend and you took advantage of that. My heart is forever broken, I will never be the same person I was before I lost Kolton. My whole life has been ruined,” she said.
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In 2016, Schreffler entered a plea deal reducing her charges to armed robbery in exchange for her testimony against the three other suspects if the case went to trial.
Another suspect, Jordan Coleman, pleaded guilty to second-degree murder and was sentenced to 25 years in Florida state prison in July 2018.
Taurean Johnson and Ozell McNabb Jr., who were accused of robbing and killing Shearer, pleaded guilty to second-degree murder in February.
They were sentenced to more than 25 years in prison.